I feel like it's probably PSX or PS2, though I don't know the exact percent. Here's why. For Atari, most of the games don't even have a real "completion," so the percent can't be very high. For NES, they call it "Nintendo hard" for a reason. I did not complete most games on the NES. For SNES were getting higher. The games were generally less hard and I started leaning more into RPGs here, which pretty much could always be beaten easily with some grinding. There are still a number of games I didn't beat, but at least we're definitely well above the 50% mark here, which is not true of the previous two consoles. PSX is where I started almost exclusively playing RPGs. There are some games my siblings had that I didn't beat, but I may actually have 100% for games that were mine. If not, I'm sure it was over 90%. However, this number would be brought down significantly if you count PSX games I bought digitally on PS3. PS2 I was pretty much whole hog RPG and again I think I finished nearly every game I bought. I think there were a couple near the end of the console life I didn't finish because I packed up my PS2 to move and now it's in my parents garage. I had to travel a little too light when I first moved and never got that stuff back. I'd say PS2 is around 90% though for sure, but again it's lower if you count digital games on PS3. PS3 - this is very low, at least if you count digital PSX and PS2 games, and probably kind of low even if you don't. PS4 - Also pretty bad. The PS3 and PS4 periods were ones in which I bought games without having finished previous ones and developed quite a backlog. They might even be worse than NES for that reason, even though the games are not NES hard. Switch is pretty bad too.